JPS6033983B2 - Power system of single-shaft gas turbine engine for vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wheel power system of the single-shaft gas turbine engine type, and more particularly to a wheel power system with automatic engine speed and transmission ratio control. be.

A turbine engine that has a power turbine rotor coupled directly to a compressor rotor for rotation therewith is referred to as a single-shaft gas turbine engine.

Because of their low initial cost and high reliability, such engines are widely used in constant speed applications such as power generation. However, such a curve representing the change in torque versus engine speed has a narrow peak with a steep slope. As a result, single-shaft gas turbine engines typically run between 50,000 and 700 mph per minute.
Maximum torque and power is produced at engine speeds in the 00 RPM range. This engine speed that produces maximum torque and power is now referred to as 100% rated speed, and as the engine speed increases or decreases from 100% rated speed, torque and power decrease rapidly. Because of this torque-speed characteristic, single-shaft gas turbine engines have not been widely used in vehicle applications requiring a fairly wide continuous operating speed range. However, single-shaft gas turbine engines can be advantageously used in wheel power systems when connected to infinitely variable transmissions. With appropriate control mechanisms, such mechanisms can maintain a controlled transmission ratio to provide engine operation at 100% rated speed under sufficient load conditions. Under part load conditions, the transmission ratio is continuously adjusted to optimize part load fuel consumption regardless of vehicle speed. The automatic control system of such a mechanism was discussed at the Society of Automotive Engineers' Midterm Conference held in Montreal, Quebec, Canada from June 7th to 11th, 1971.
It was proposed at the Mid-Year Meeting).
This proposal was submitted by Mr. Bernard E. Pore in the Society of Automotive Engineers Bulletin No. 710551 entitled "Control system for single-shaft gas turbine engine type vehicles".
ols targetr Synge ShaftGas Tmb
ine Vehicles” by Shigeru AsahirdE.Po
ore). The present invention is a further improvement on the type of power system described above.

For example, the energy required to start an axle gas turbine engine is considerable. Single shaft gas turbine engines typically need to be accelerated to about 55% of rated speed before engine operation will automatically continue. At this speed, the engine rotates at several thousand revolutions per minute and the rotating parts of the engine possess significant kinetic energy. The engine starting system must supply not only this kinetic energy, but also energy to overcome the friction of the engine and to drive the engine's accessories and their drive gears. service·
Connecting the vehicle accessories "behind" the clutch means that the operation of these accessories is interrupted each time the service clutch is disengaged. This is undesirable and unnecessary for accessories such as air conditioning compressors, and is probably unacceptable for accessories such as alternators, hydraulic pumps, or air compressors. Furthermore, under high load conditions where the wheel operator expects automatic operation, an automatically controlled turbine power system will have somewhat more engine stalls and overload conditions will require the operator to reduce the overload. Stall the engine without taking action. If the engine stalls, there is a significant delay in starting the engine again and, as previously mentioned, a significant strain is placed on the starting system. Another problem with known wheel turbine power systems is that they provide an inadequate indication of the operating status of the wheels.

In prior art gasoline or diesel engines, there is a substantial relationship between engine speed and wheel load. The tachometer display is therefore sufficient to make wheel driving adequate. However, when a wheelbarrow is powered by a turbine engine and an infinitely variable transmission with an automatic control system, there is little relationship between engine speed and wheel speed. Therefore, it is desirable to further display the load status of the tomb in some way.
The power system of the gas turbine engine for a car cocoon according to the present invention includes a monotonous gas turbine that supplies rotational energy, an automatic clutch connected to receive rotational energy from the engine and output this energy as output, and a driver. A service clutch is connected to receive rotational energy from the output of an automatic clutch that is selectively applied by the automatic clutch and output this energy as an output, and a service clutch that receives rotational energy output from the service clutch and rotates at a variable torque ratio for driving the wheels. It includes an infinitely variable transmission connected to output energy and a wheel control mechanism.

The follow-up control mechanism is connected to control engine speed, transmission ratio, and automatic clutch disengagement in response to engine and wheel speed commands from the driver. The car load meter displays the car load condition as well as the engine speed in a continuous range of readings. In the manual mode of operation, the control mechanism is such that an engine speed control lever is advanced to maintain the engine operating at the speed indicated by the lever.

A transmission ratio is commanded that maintains the wheel speed indicated by the wheel speed lever, except that the wheel speed is reduced if sufficient power is not available at the commanded engine speed. Automatic mode, represented by placing the engine speed lever in the neutral position, commands the transmission ratio to maintain the wheel speed as selected by the speed control lever when sufficient power is available. Engine speed is controlled in response to exhaust temperature and engine speed feedback to optimize fuel consumption at 100% rated speed under full load conditions and under part load conditions. The automatic clutch is controlled to automatically disengage at engine speeds below 55% of rated speed and automatically engage at engine speeds above 55% of rated speed.

This combined speed is selected to be slightly above the stall speed below which engine operation is automatically maintained but below the normal idle speed. Manual I
The memory circuit prevents IJ mit cycling under overload conditions by preventing the automatic clutch from disengaging and then re-engaging until reset by the J-set switch. reset. The switch can be suitably made as part of the starting switch so that it can be automatically reset upon starting. By connecting essential engine-driven accessories, such as a fuel pump or oil pump, in front of the automatic clutch and connecting non-essential accessories behind the automatic clutch, the load on the starting system will be removed from the non-essential accessories automatically. is greatly reduced during startup by being left disconnected (suspended). However, once normal operating speeds are reached, non-essential auxiliary equipment is driven in the conventional manner without interruption. The automatic clutch also acts to prevent the engine from stalling in the event of an overload condition. This prevents additional friction in the starting system and prevents long delays during restarts.The wheel load meters display several load readings in response to a decrease in engine speed and wheel speed. It acts to indicate the load status with a visual display that continuously increases in value over a range.

The display is provided by a simple meter with a pointer that is rotated in proportion to the value of the input signal. In the lower display range, part load engine speed is either 0% or 100% of rated speed.
will be displayed up to. This meter thus functions as a conventional tachometer in the lower display range. In the automatic operating mode, as the load demand of the car is increased, the operating speed of the engine is first increased to 100% rated speed.Then, while the engine is maintained at 100% rated speed. "The transmission ratio is reduced to reduce the load by reducing the wheel speed until the load increases further and the load demand matches the engine power. The intermediate meter indication range is This decrease in ground speed is indicated by adding an engine signal N, which indicates 100% engine speed in this operating range, to an error signal C, ERROR, which indicates the difference between the speed and the actual speed.The gain of the ground speed error signal. is 100% as the lower limit of the intermediate range.
From the rated speed display, the ground speed decreases by 50% of the command speed.
%, it indicates the maximum amount of decrease as the upper limit of the intermediate range. Ground speed reduced by 50%
As this is reached, safety features of the control system act to prevent further reduction in the transmission ratio.

This safety feature ensures that the demand ground speed is not accidentally set to more than twice the actual ground speed. Therefore, excessive acceleration is prevented when the overload condition disappears. If the reduction in ground speed exceeds 50%, the engine speed is reduced and the normally small engine speed error signal that controls fuel flow begins to increase.
A limit circuit senses this increase in engine speed error signal and clamps the engine speed signal at 100%.
Therefore, this increase in engine speed signal causes the display to increase in magnitude across the higher range display when a decrease in engine speed occurs. The 55% engine speed at which the automatic overload clutch disengages can be marked on the meter scale in the upper range and the stall speed can be marked on the meter scale beyond the point of the automatic clutch. Therefore, it operates in an automatic mode to indicate the load condition of the wheel bran, which is more useful than a simple tachometer display.

In manual operating mode, the make acts as a tachometer within the lower display range. As shown in FIG. 1, a single-shaft gas turbine engine power system 1 for a vehicle according to the present invention, a vehicle control system 12, and intermediate elements between the power train and the driver related thereto. Contains.

The power train includes a single-shaft gas turbine engine 14, a planetary gear reduction gear 16, and a drive gear 18 for essential accessory equipment.
It includes an automatic clutch 20, a reduction-non-essential accessory gear drive 22, a service clutch 24, and an infinitely variable transmission 26. The infinitely variable transmission 26 is connected to drive the wheels of the wheels in a conventional manner, such as from a differential rear end. It includes a controller 30, a load meter 32, a speedometer 34, and a switch 33. and a single power turbine.

Such engines have a curve representing torque as a function of engine speed with a rather steep, narrow peak. Therefore, in order to obtain significant power from the engine, it is necessary to operate the engine over a relatively narrow speed range. The speed of the engine is controlled in a dependent manner by regulating the flow of engine fuel in response to a fuel command signal that is proportional to the difference between the commanded speed and the actual engine speed.
As the fuel command signal increases in magnitude, the flow of fuel increases and engine 14 provides more power. If load conditions permit, a decrease in N, the error signal increases the fuel command signal,
This increased power therefore accelerates the engine until a reduction in fuel flow is commanded. Three primary engine status signals are communicated from engine 14 to wheel control mechanism 12.

These signals are an intake air temperature signal T, an exhaust temperature signal L, and an engine tachometer or speed signal N. A planetary speed reducer 16, which may be conventional in nature, receives high speed rotational energy from the turbine engine 14 and produces a reduction ratio of approximately 5 to 1 and a corresponding torque. The output of the turbine engine 14 is about 60,000 rpm and the rotational speed is about 70,000 rpm, and the output of the reduction gear 16 is about 12,000 rpm.
000 rpm. A requisite accessory gear drive 18 is connected to receive rotational energy from the reduction gear 16 and produce mechanical energy to drive the requisite accessory. Power output to engine 14 is illustrated to drive the fuel pump and lubricant. Another example of an essential accessory device is a drive mechanism for power brakes or power steering. The accessory calendar, driven by the essential accessory drive 18, is directly and continuously connected to the engine 14 and is energized as long as the engine 14 is operating. The automatic clutch 20' is connected to receive rotational energy from the essential accessory drive 18 and supply rotational energy to a reduction and non-essential accessory gear drive 22. By directly connecting the automatic clutch 20 and accessory gear drive 18 to the planetary speed reducer 16 through separate parallel power paths rather than in series as shown, it is easy to slightly change the power train. There are some things you need to understand. In either case, both the automatic clutch 20 and the essential accessory gearing 18 are directly and continuously connected to receive rotational energy from the turbine engine 14. automatic clutch 2
0 engagement and disengagement are controlled by clutch control signals generated by the wheel control system 12. It is anticipated that under normal operating circumstances, automatic clutch 20 will need to remain engaged continuously. However, a clutch control signal can be generated to disengage automatic clutch 20 during start-up conditions and emergency overload conditions. Turbine for starting
The turbine engine typically must be accelerated to a speed of about 55% of maximum torque speed before engine operation can be automatically sustained.

The engine starting mechanism must be able to supply a significant amount of energy to overcome the inertia and friction loads of the rotating parts when these high speeds are reached.
Disengagement of the automatic clutch 20 typically allows this inertia and friction load to be reduced by requiring drive during startup of the starter and essential accessories, respectively.
The energy that needs to be supplied by the starting mechanism is therefore greatly reduced. Automatic clutch 20 can also be disengaged to prevent the engine from stalling during emergency overload conditions. For example, if the wheel control mechanism 12 is the signal N,
It is necessary to monitor the operating speed of the engine shown in and generate a clutch control signal that disengages the clutch when the engine speed decreases to a speed very close to the engine stall speed, which is approximately 55% of the engine speed. is expected.
When the automatic clutch 20 is disengaged, the overload condition is detected by the engine 14.
allows the vehicle to accelerate without stalling. Normal about 3
The load demands on the starting mechanism due to sand delays and the associated extra starting are avoided. To limit cycling to overload conditions, once the automatic clutch is disengaged, the clutch control mechanism prevents further engagement of the clutch until the clutch reset signal provided by switch 33 is activated. The switch 33 is advantageously provided as part of a conventional ignition switch for wheels. A reduction and non-essential accessory drive gearing 22 is connected to receive rotational energy output from automatic clutch 20 and drive service clutch 24 .

Drive gearing 22 also provides mechanical energy to drive non-essential vehicle accessories such as, for example, an air conditioning compressor, a hydraulic pump, a lubricant cooling fan, and an air compressor. Of course, other auxiliary devices can be provided as required depending on the nature and purpose of the vehicle alert. Service clutch 24 is a prior art operator controllable clutch that selectively connects the transmission to the engine. For some wheels with automatic transmissions, a service clutch may not be necessary. In other vehicles, such as standard tillage tractors, it may even be desirable to utilize a service clutch 24 in conjunction with an automatic transmission. The infinitely variable transmission device 26 is a service. A clutch 24 is connected to receive rotational energy from the clutch when selectively engaged and to supply rotational energy to the primary wheel drive mechanism at a variable torque ratio. For example, infinitely variable transmission 26 may be selected to drive selected wheels of the vehicle with fixed or selectively variable discrete gear ratios. An infinitely variable transmission 28' is shown providing an actual ground speed indication signal G, to the vehicle control mechanism. Due to the constant gear ratio between the output of the transmission 26 and the drive wheels of the wheel, the signal G, is directly proportional to the rotational speed at the output of the transmission 26. If the transmission 26 is connected to a variable gear ratio system, it is necessary to generate the signal G from elsewhere or to vary the signal C according to the selected gear ratio. Infinitely variable transmission 28'
Although finite, the ratio signal R generated by the gear control mechanism provides a gear ratio that is variable over a proportional continuous ratio range. The transmission 26, which is conventional in nature, has a relatively long response time compared to the response time of the wheel control transverse 12. The error between the gear ratio commanded by signal R and the actual gear ratio is therefore very small (less than 5%).
The rotational speed control mechanism ensures that the actual gear ratio is the same as the commanded gear ratio. When the infinitely variable transmission system 6 is used when a significant difference occurs between the commanded gear ratio and the actual gear ratio, an addition is made to indicate to the wheel control mechanism 12 the actual gear ratio of the transmission 26. It may be desirable to provide an input signal of Engine speed controller 28 operates in a manner similar to prior art manually controlled wheel throttles.

The engine speed controller has a combination of manual and automatic switches which indicate an automatic mode of operation when the engine speed controller is in the inactive position and a manual mode when the engine speed controller is in the active position. Generates an M-A signal indicating the operating mode. When activated, the engine speed controller generates an engine speed command signal N, which causes the wheel control mechanism 2 to operate, if possible, to maintain the engine speed at the specified speed.Ground speed controller 3
0 can be operated independently or in conjunction with engine speed controller 28. Ground speed controller 3Q'
A signal G, set proportional to the position is supplied. In the manual mode of operation, the signal G, set acts approximately as a gear ratio command signal. The infinitely variable transmission 26 and the wheel control transverse 12 act to produce a gear ratio proportional to a certain gear ratio, thus signal C, set. The engine speed controller 28' is automatically reduced when the commanded engine speed cannot provide sufficient power to maintain the commanded ground speed.
The ground speed controller 381 is inactive, and the wheels are operated by the ground speed controller 381.
Only in this way can it be controlled.

In this automatic mode of operation, the G, set signal acts only as a ground speed command signal. If sufficient power is available, the wheel speed control mechanism operates to accelerate the vehicle along a predetermined acceleration curve to a commanded ground speed. In the automatic mode of operation, the wheel control mechanism controls the transmission ratio and engine speed simultaneously and in conjunction with each other to operate the engine near its most effective operating point for a given load condition. No attempt is made to maintain any particular engine speed. If sufficient power is not available,
The wheel control mechanism ensures that the actual speed is 50% of the commanded speed.
%. If the speed needs to be further reduced in light of the available engine power, an overload condition occurs. This deceleration limit prevents the ground speed controller 30 from unnecessarily advancing to a relatively high commanded speed while the car is operating at a relatively low speed due to heavy load conditions. If such a large discrepancy is allowed to occur between the commanded signal and the actual ground speed, the wheels may rapidly accelerate to the commanded speed when the load is removed. If the chariot is in a potentially dangerous situation that the driver anticipates requiring the wheels to continue at a low speed, such rapid acceleration may cause an accident. Therefore, ``the deceleration limit is 2 to 1 or more.
It works to prevent this from occurring without being manipulated. Other driver-facing elements include a load meter 32 and a speed 34.

Speedometer 34 is a prior art ground speed indicator that operates in response to signal G. Load meter 32 is a relatively complex instrument that displays a combination of engine speed and engine load depending on the specific operating conditions of the garage. This instrument will be described in detail later. Referring to FIG. 2, a portion of the power system 10 of the car mackerel engine is shown in detail.

For clarity and simplicity, prior art features of wheel control mechanisms, such as engine start and no-load operation controllers, have been omitted or simplified. However, it must be assumed that these prior art features, although not explicitly shown, are incorporated into this control mechanism. Furthermore, gain changing elements such as operational amplifiers are not explicitly shown. however,
It will be appreciated by those skilled in the art that conventional gain control elements may be added to the signal path as desired to suitably adjust the signal amplification. In the manual mode of operation, the engine speed lever within the engine speed controller 28 is advanced and an engine speed signal set 35 proportional to the advanced position of the lever is generated. The engine speed signal set is combined with the temperature speed control signal 36 to produce an uncompensated engine speed control signal 37. A lag compensator 38 receives the uncompensated engine speed control signal 37 and generates an engine speed command signal 39.
The lag compensator 38 closely matches the time rate of change of the engine speed command signal 39 to the acceleration of the engine 14 to make it more stable. In the manual mode of operation, mode control switch 40, such as a relay or electronic switch, is held open by signal M-A and engine speed command signal 39 approximately represents the forward position of the engine speed control lever within engine speed control mechanism 12. . By subtracting the actual engine speed signal N, from the engine speed command signal 39, a negative feedback loop for controlling engine speed is completed to generate an uncompensated engine speed error signal 42.

Engine speed error signal 4 with uncompensated compensation element 44
2 by a proportional gain, preferably a combination of the proportional gain and an uncompensated engine speed error signal 42, to control the amount of fuel delivered to the engine 14 under normal operating conditions. N that actually controls the speed
, generates an ERROR signal. A minimum signal selector 50 receives a plurality of different signals including the N and ERROR signals, and sends the smallest signal among these control signals to the engine 14 via a maximum signal selector 53 as a fuel control signal.

The N,ERROR signal is a normal control signal, and the other signals are safety, ie, precautionary signals. For example, F, functional element 54 receives the fuel output signal N, and ignites the engine at any particular engine speed according to a predetermined maximum fuel schedule.
a maximum fuel signal 55 that limits the flow rate of fuel that can be supplied to 4;
occurs. For example, since the maximum fuel schedule is one limit and not a normal control, this schedule can be implemented in the circuit shown in FIG. can. The summing amplifier 56a is connected to the voltage holding intersection 57
Since the feedback resistor R is driven by setting the voltage to the ground potential, the output voltage is V5&out:-(N, 10VP,). In that case the maximum fuel signal 55 is V5 out=(
RFb/R2)·(N, 10VF,). More complex maximum fuel schedules are of course possible if desired. A temperature limited fuel signal 58 is generated by F2 function element 60 in response to the engine temperature signal.
A temperature sensor 64 senses the exhaust gas temperature and the intake air temperature and generates an engine temperature signal T5 that is approximately representative of the exhaust temperature and a signal T that is representative of the intake air temperature. As the sensed intake air temperature increases, the engine temperature signal T5 is pulled down somewhat by the signal T, causing the engine 14 temperature to rise on a hot day.
Allow it to heat up somewhat so you can drive it. F2 function element 6
0 is about 675oo from the adjusted exhaust temperature T5ADJ (
Overheating of engine 14 is prevented by subtracting signal V1250 indicating a temperature of 12,500F. This difference is subtracted from the low temperature output voltage V low only when this difference is positive. For example, temperature limited fuel signal 58 may remain at a maximum value V low until signal LADJ indicates a regulated exhaust temperature of approximately 67,500 degrees (12,500 degrees Fahrenheit). As the exhaust temperature signal continues to increase, the temperature limit fuel signal is proportionally decreased and the engine temperature signal increases to indicate a regulated exhaust temperature of approximately 70,500 degrees (13,000 degrees Fahrenheit) and the fuel supply to the engine 14 is interrupted. Cut it off completely. The circuit for F2 function element 60 is shown in FIG.

An amplifier 58a receives the inlet gas temperature signal T, and outputs a voltage V5 used to adjust the exhaust temperature signal out=-
generates an output signal having T, (R4a/R4). The adjustment is determined by the gain R4a/R4. For example, if this gain is assumed to be 1/2 in this example, then the exhaust temperature T
5, the temperature can be increased by 1/degree for every 1 degree increase in inlet gas temperature. The operational amplifier 58b is connected as a summing amplifier that generates an output voltage -GADJ=(750V5out)=-(75-T, (R4a/R4).If diode D4 is temporarily ignored, the effect The amplifier also output voltage V5 out = peak (1 T5 ADJ + V1250) R4
It is also connected as a summing amplifier that generates c/R4=R4c/R4 (T5ADJ-V1250). voltage y125
0 is approximately 67,500 (12,500F) when fuel starts to decrease
is selected to balance signal T5ADJ with the adjusted exhaust temperature of . The gain R4c/R4 is approximately 1000 (50
0F) is selected to change the output voltage V5$out by a voltage equal to the voltage Vlow as the signal T5ADJ changes in response to a change in the exhaust temperature. Signal 5AD
Unless J exhibits an exhaust temperature above about 67,500 (12,500 F), it will substantially block the output voltage V5&out. Another operational amplifier 58d also provides a temperature limited fuel signal 58=-(V
It is connected as a summing amplifier that generates 5 out - V low ) = V low - V5 out. At low exhaust temperatures, the output V5&out is nearly zero and the temperature controlled fuel signal 58=V low allows significant fuel flow.
If the regulated exhaust temperature is approximately 67,500 (12,500
F), the signal 58V low-V5 &
out2V low-R4C/R4 (LADJ-V1
250). A maximum signal selector 53 receives the flow control signal 52, which is a normal fuel flow control signal in addition to the minimum fuel flow schedule signal, and passes the larger of the two signals as the fuel control signal modified to control fuel flow. .

The minimum flow schedule signal from F,A function element 65 ensures that adequate fuel flows for startup and no-load operation. If desired, the function can be made more complex, but the minimum flow schedule signal can increase linearly with engine speed and decrease somewhat as T increases (mass flow decreases). A typical functional relationship is:
MFS=(M)(N,)+P(Q-T,)=(M)(N
, ) + (P) (Q) - (P) (T,) In the above equation, MFS is the maximum fuel flow schedule signal, and P and Q represent the specific combustion efficiency and engine performance. It is a constant chosen to give the best result.

The F,N function element 65 is the F,N function element 54 shown in FIG.
Addition and amplification circuits similar to those configuring can be suitably constructed. An emergency shutdown element 66 monitors for conditions that could damage the engine and generates an emergency fuel control signal 68 that is normally high but drops to zero to shut down the engine when an emergency condition is detected.

For example, an emergency shutdown element 66 may result in a 110% engine overload condition where the exhaust temperature does not become too high or a proper starting sequence occurs, but it may be desirable to monitor for loss of oil pressure, etc. The engine will be stopped in the event of an emergency situation. The emergency fuel control signal 68 is communicated to a solenoid valve 69 which is connected to interrupt the supply of fuel to the engine when the signal 68 is de-energized by going low. Therefore, engine speed controller 2
8 is in hand-sardine mode and operates almost regardless of the condition of the other wheels.

The engine speed controller 28 can advantageously be used to provide power when the vehicle is stationary, such as when powering a deep plow tractor or dumping from a dump truck. However, when the ground speed controller 30 is energized at the same time, the engine speed controller 28 also controls the engine speed, thus controlling the speed of the vehicle in a manner very similar to controlling speed with a throttle in a normal automobile with an automatic transmission. It can also be used to change the bran speed. In a single shaft gas turbine engine, the engine's output power and torque are maximum at 100% rated speed and rapidly decrease as the engine speed increases above but below 100% rated speed. Therefore,
Proper control of engine speed is very important in controlling vehicles having single shaft gas turbine engines. If the ground speed controller 30 is actuated, for example, by the advancement of a control lever arm during operation during a manual actuation mode, a ground speed set signal 76 will be generated in proportion to the position of the lever. It will be done.

This signal acts as a transmission ratio selector in manual mode. The ground speed set signal is communicated to F3 function element 78, which responds by generating a ground speed command signal 80. F3 function element 78 is ground speed set signal 7 except that ground speed command signal 80 allows this command to increase in magnitude only as a ramp function with a predetermined slope.
Have them follow the same pattern as 6. The slope of this ramp function is adjusted to be proportional to the ability of the engine 14 to accelerate the vehicle and defines the rate of increase in wheel ground speed as long as the power capability of the engine 14 is not exceeded. FIG. 5 shows a circuit that produces the signal relationships described above. When the voltage of the set signal changes, the diode Z3A or Z3B
Connect the 3A output to resistor RS3 or RS3 depending on the polarity.
It acts as a reference voltage over ten ranges. Therefore, it changes depending on the slope of amplifier A3B.

RS30 defines the slope of the ramp function that goes positive, while RS3
1 determines the slope of Enoki's slope going negative. By selecting RS3-C sufficiently small, changes in command signal 80' and set signal 76 can be followed almost instantaneously. ZV is the sum of the Zener breakdown voltage and the forward diode voltage drop across diodes Z3A and Z3B. Amplifier A3 aging signal 80 key Just provides negative feedback to the outer loop so that it can follow the set signal 76 with a cage gain under steady state conditions.

The ground speed command signal 8 is conveyed to summing junction 82, and a negative feedback loop controlling the transmission ratio is completed by subtracting signal R, which is proportional to and indicative of the transmission ratio.

In the absence of other factors, the ground speed command signal will therefore increase at a predetermined slope when the ground speed controller 80 is activated and the control loop will adjust the transmission ratio to the commanded slope from the speed command signal 8. Increase approximately along. If engine speed remains constant during this ramp period, the wheel ground speed will also accelerate approximately to accommodate this ramp. However, the wheels may be pulling an unusually heavy load or In some cases, the vehicle may be set to a position where no significant engine power is generated. In such a situation, sufficient engine power may not be available for the driver to accelerate along the slope commanded by the ground speed command signal 801. In the absence of other control signals, engine 14 cannot meet the power demand and stalls. However, if the requested power exceeds the power that engine 14 can provide, additional negative feedback is added to junction 82. This reduces the transmission ratio and, therefore, the power demand of the engine 14.

Functional element 84 responds to engine speed command signal 38 by generating a modified engine speed command signal 86 . By allowing the modified engine speed command signal 86 to increase only along a ramp function, abrupt reductions in transmission are avoided for stability purposes. The modified engine speed command signal 86 can quickly follow a one step reduction in the function of the engine speed command signal 39. The structure of the F4 function element 84 may be substantially the same as the F3 function element 78 shown in FIG. A summing junction 90 receives the modified engine speed command speed signal 86 as a negative feedback input and generates a transmission control engine speed signal 92 as an output. F5 function element 94 receives transmission control engine speed error signal 92 and generates a rate reduction signal 96 in response thereto.

The ratio reduction signal is not allowed to go negative so as not to increase the transmission ratio, and for stability reasons, the ratio reduction signal 96 only controls transmission control if the transmission control engine speed error signal is positive and does not exceed a predetermined critical magnitude. Tracks engine speed error signal 92. Otherwise, the ratio reduction signal 96 has zero magnitude and does not affect the transmission ratio. A concrete example of the F5 function element 94 is shown in FIG. Schmidt when signal 92 exceeds criticality. The trigger closes switch SW5. It has been found that setting the critical magnitude to about 2% provides adequate stability and excellent response characteristics. That is,
When the actual engine speed NI becomes less than 98% of the commanded engine speed indicated by the modified engine speed command signal 86, the ratio reduction signal 96 is activated. Accordingly, if the load demand of engine 14 exceeds its power capability, the engine speed will fall below demand and a ratio reduction signal 96 will be generated to reduce the transmission ratio and, therefore, the load demand. The actual transmission ratio is commanded by the transmission ratio signal R generated as the output of the maximum signal selector 100.

Under normal circumstances, signal R is generated by linear amplification of the ratio error signal 102, which is generated as the sum of the inputs to summing junction 82. The maximum signal selector 100 is a circuit that receives a plurality of inputs and generates one input having the maximum magnitude. The actuator in the transmission device 20 is capable of following a commanded transmission ratio that is fast compared to the acceleration of the engine 14, and accurately represents both the commanded transmission ratio and the actual transmission ratio with the signal R'. considered to be. In the automatic operating mode, the engine speed set signal 30 remains zero and switch 4 remains closed continuously allowing the temperature and speed control signal 36 to command the engine speed. The F2 function element 60' is derived from the adjusted exhaust temperature signal - T5ADJ, and is generated by the F6 function element 12M.
) Automatically controls engine operation to moderate fuel savings by maintaining exhaust temperature at or near maximum temperature.

In a first functional relationship, shown by curve F6 in FIG.
Clamped at 0%. Under this environment, the engine blade 4 is allowed to operate unloaded at 60% of its rated speed.
As the regulated exhaust temperature increases above approximately 28,900 (6000 F), the warm bird speed control signal 36 will increase to 100% of the rated speed when the regulated exhaust temperature reaches the maximum allowable temperature of approximately 675 o 0 (12,500 F). The humidity is proportionally increased to a level sufficient to command maximum humidity. At maximum exhaust temperature, fuel consumption reaches a certain basic minimum (preferred fuel efficiency). This first of F6 function elements
The arrangement allows the engine to be automatically operated near a high exhaust temperature for favorable fuel consumption at significant loads. When the engine 14 is subjected to an increased load during no-load or partial operation, the temperature of the exhaust increases and an increased operating speed is commanded.

As the commanded operating speed exceeds the actual speed, an error signal is generated which causes the engine 14 to supply more fuel. The engine 14 responds by accelerating until the exhaust temperature decreases to reduce the commanded operating speed. Therefore, the increased power output seeks increased operating speed to match the increased power demand. A circuit for generating the functional relationship of the F6 functional elements is shown in FIG.

An operational amplifier 121 is connected to the summing amplifier to produce the output voltage. Adjusted exhaust temperature is approximately 289%
If it is in the range of 67500 (without 600, and i2500F), F
5 ADJ + V600)) = RF6/R6 (V60% + T
5ADJ-V600).

Below approximately 28900°C (6000F), one T5ADJ causes diode D6 to be biased in the opposite direction and the output voltage F6o
Since ut is clamped to F=(RF6-R6)V60%, it does not affect the operation of the circuit. Approximately 67
Above 12500 F., resistor RLS and zener diode dish T are activated to clamp the output voltage to the zener breakdown voltage that needs to be selected to indicate 100% engine speed. The circuit gain is -T5ADJ is approximately 2
Approximately 67500 (12
The output changes from 60% to 1 as the display changes to 500F).
It is necessary to select to change the engine speed command to 00%. Voltage -V60% if V600 is about 2890
Signal at regulated exhaust temperature of C (at 600) - T5A
Minimum 6 in terms of circuit gain when equal to DJ voltage
The 0% output signal must be chosen to be equal to the voltage of battery B6 plus the forward conduction voltage drop of diode OS. The proportional curve F6 is shown in Figure 7 as the curve F6'.
By modifying it to be somewhat steeper, as shown in Figure 1, the operating speed of the engine can be biased towards a higher temperature (lower speed) operating point that slightly improves fuel efficiency.

This second register of F6 function elements 120 has approximately 67,500
The gain RF6/R6 is increased to make the signal equal to T5ADJ at a temperature of (12500F) and the voltage V60
0 is incremented. This second arrangement is a single shaft turbine. Operating the engine 14 closer to exhaust temperature limits under part load conditions improves steady state part load fuel consumption efficiency. However, higher gain reduces the stability of the operating point and causes engine 14 to accelerate and decelerate more. A third arrangement intermediate between the high efficiency at moderate loads obtained by curve F6' and the higher stability of curve F6 is shown in FIG. 7 by curve F6''.

This functional relationship is shown in Figure 8 between battery B6 and diode D.
6 can be roughly obtained by using the circuit shown in FIG. A signal LADJ is referenced by battery B6 and diode D7 to apply a negative voltage to the input to amplifier circuit 121a starting from 0 volts as operational amplifier 121a regulated exhaust temperature exceeds approximately 289°C (6000F). It is connected as an inverting amplifier that changes the gain of the amplifier.

The gain RF gold/R6 of the amplifier 121a is approximately 67500 (1
The output voltage is selected to produce an output voltage less than or equal to about 1.2 volts at a temperature of 2500F. amplifier 1
The output side of 21a is connected to the input side of another inverting amplifier circuit 121b via two diodes ○6a and D6b. The diodes ○6a and D6b pass a current having an exponential relationship with the output voltage from the amplifier 121a. Feedback resistor RF6b controls the gain of amplifier 121b, which generates an output voltage proportional to the current flowing through diodes D6a, D6b. Resistor RF6b should be selected to produce an output voltage that corresponds to the voltage at the anode of diode D6 shown in FIG. 8 when signal -T5ADJ indicates approximately 675 DEG C. (12500 F.). Regardless of which configuration is chosen for the F6 function element, the automatic controller operates the engine 14 at a speed that maintains a relatively high exhaust temperature and produces adequate fuel efficiency for the particular load condition. This is in contrast to manual constant speed operation in response to an engine speed controller 28 that follows a commanded signal regardless of fuel efficiency. The transmission is controlled by switching switch 1 in response to the automatic display of the M-A signal.
The automatic operating mode is substantially the same as the manual operating mode except that 30 is closed and adds an external ground speed error loop to the transmission ratio control mechanism. This is done by subtracting the actual ground speed of G from the ground speed set signal 76 and applying the difference as a positive input 132 to the general junction 82. The magnitude of the G,ERROR signal remains relatively small compared to the magnitudes of the ground speed command signal 80 and the ratio signal 86.
The R signal has minimal effect on the transmission ratio R during transient operating conditions. Once these other signals are approximately balanced with the transmission ratio signal, the G,ERROR signal acts as a precision tuning signal that more accurately controls the actual ground speed. F7 function element 134 cooperates with maximum signal selector 100 to provide special safety characteristics to wheel power system 101.

Under fully loaded conditions, the ground speed of the wheels is controlled by adjusting the transmission ratio to match the wheel load to the available power. For example, a tractor that plows hard ground is 1
The ground speed controller 30 is set to a ground speed of approximately 18 miles per hour, while the available power allows only a ground speed of approximately 1 mile per hour. . In such an environment, the ground speed controller 30' can be hit by the driver without noticing, and the ground speed controller 30' can be
You may think that the ground speed controller 30 is set to about 4.83 mph (3 miles) when it is set to 8.97 mph (18 mph). Under these circumstances, when the load is removed from the truck by, for example, raising the plow off the ground at the end of the girth, approximately 28.97 ribs (18 miles) per hour will be removed from the truck. Accelerate to maximum speed. Such rapid and unexpected acceleration can cause the tractor operator to lose control of the tractor and, if the tractor is close to a ditch or building, can result in damage to the tractor before it can be regained control.
The low speed control circuit avoids this potential damage to the tractor by providing a transmission ratio override signal 136 in response to the ground speed controller.

Transmission ratio override signal 136 commands a transmission ratio R that results in an actual ground speed of approximately 50% of the ground speed indicated by ground speed command signal 80 at 100% engine speed. max signal detector io
o operates by allowing the transmission ratio override signal 136 to act only when its magnitude is greater than or equal to the signal R generated in response to the transmission ratio error signal 102.

The circuit that makes up the F7 functional element 134 consists of two resistors, a signal 80 and a signal 1 taken from the common junction of these resistors.
36 diodes connected in sequence to ground. This diode produces a slight residual deviation to improve the operating characteristics at zero wheel speed. Under normal circumstances, the engine 14 has sufficient power to maintain the car at more than half the commanded speed and the low speed limit circuit has no effect on the operation of the car. However, if a large load is applied to the wheels, the transmission ratio R
The reduction in ground speed resulting from a decrease in ground speed is limited by the low speed limit circuit to 50% of the commanded ground speed. Under these circumstances, the engine 14 will not develop sufficient torque to overcome the load and will decelerate to near stall conditions unless the commanded vehicle speed is reduced. If the infinitely variable transmission 26 is a non-slip type with an infinitely variable ratio up to R=0, then the service clutch 24 must be used for stopping.

Furthermore, there is a need to prevent the possibility of infinite torque ratios between the engine and the drive wheels. For such a transmission device, a lower limit of the transmission ratio is determined so that the constant voltage signal RMIN can be input to the maximum signal selector 18Q. This ratio is service. When servicing the wheels or applying the brakes to stop the wheels without disengaging the clutch, it is necessary to choose to overload the engine and stall before mechanical losses are incurred by the power train. Another feature of the wheel power system Q is an automatic clutch 28 which is controlled in response to a clutch control signal 52 generated by an automatic clutch circuit in response to an actual engine speed signal N.

Whenever signal N, indicates an actual engine speed below 55% of rated speed with no load and the engine very close to a stall condition, automatic clutch control circuit wealth 54 senses this low signal condition and activates automatic clutch color 58. A clutch control signal 152 is generated to command the release of the clutch. When the automatic clutch 20 disengages, most of the load is removed from the engine 14 and the engine
% normal no-load operating speed. A memory circuit such as a flip-flop in the automatic clutch control circuit 154 stores the clutch control signal turtle 52 in the automatic clutch 2.
Every time Q is removed, it is set and the memory circuit becomes a clutch. Clutch control signal 15 until reset by reset signal
2 remains in a reset state to prevent re-engaging the automatic clutch. This reset requirement is for engine 1
4 prevents a limit cycle condition in which the automatic clutch is repeatedly disengaged when accelerating above or decelerating below the 55% deceleration point. Advantageously, the clutch reset signal is generated by an ignition/start switch that allows the automatic clutch control circuit to automatically reset each time the engine 14 is started. The starting system generates a reset signal when the engine is operating under no load after the automatic clutch 20 is disengaged, so a signal N. Disabled in response. Auto-clamp prevents a total loss of power due to engine shutdown, eliminates the loss of time required to restart the engine, and reduces wear and tear on the car's battery and starting system due to repeated starts. do. As shown in FIG.
It includes a prior art doorsonval motion panel q-meter 80 having a pointer volume 82 controlled by a rotating mechanism 184 causing it to rotate in proportion to the current supplied by the meter. Current driver turtle 86 generates a current proportional to load signal 188 from switch 190. Switch turtle 9Q'M-A (in manual mode)
Manual - Automatic) Load signal seal 8 in response to mode signal
, connect to engine speed. The load meter 32 thus acts as a standard tachometer, displaying engine speed over a range of zero to 100% of rated speed in manual mode. In automatic mode, switch 19
The load signal 188 is repositioned to provide the load signal 188 from the output of the summing junction 192. The summing junction 92 outputs the ground speed error signals G, ERROR and the engine speed error signal N.
, ERROR and clamp. It receives engine speed signals N and C as inputs. During part-load and full-load engine operating conditions, the switch 194 is positioned by the actuator 196 to provide the summing junction 92 with a clamped engine speed signal equal to the actual engine speed signal N. Under normal load conditions, the load control system 32 acts as a speedometer that indicates engine speed in much the same manner as in manual operation mode.As the load increases, the automatic control system reduces the engine speed to 100%. engine speed is increased to the rated engine speed and indicator 182 is rotated to display angle 198 to display this engine speed.

As the wheels are further loaded, the power output of the engine 14 cannot be increased and is compensated by reducing the transmission ratio to provide a lower ground speed than the commanded ground speed. Due to this reduction in ground speed, the summation junction 182 increases the
N is applied to the engine speed signal, G is applied to the ERROR signal, and the indicator 182 is rotated clockwise past the 100% engine angle 198 to an overload indicating angle of 20 degrees. The gain of the G,ERROR signal will change to indicator 1 when the ground speed decreases to 50% of the commanded ground speed.
82 is selected to rotate through an overload indication angle of 200'. At this time, the F7 function element 134 is operated by the maximum signal selector 100' to prevent the ground speed from decreasing any further, as shown in FIG.

As the load on the wheel increases further, it naturally overloads the engine 14 and begins to reduce speed. As the engine 14 decelerates, the speed of the engine increases to the level commanded by the wheel control mechanism 12.
00% speed and the engine error signal N. E.R.
ROR begins to increase in size. As the signal N,ERROR exceeds the relatively small threshold normally required to operate the engine fuel valve at 100% engine speed,
Actuator m96 senses this increase and switches switch 194 to 100.
% engine speed at a voltage equal to the power of signal N. Reposition C so that it is held by the clamp.
Accordingly, summing connection 192 provides clamped engine speed signals N, C of sufficient magnitude to drive indicator 182 to the 100% display position 198 and
Overload display position 2 beyond engine speed display position 198
N,ERRO which is large enough to drive 00'
The N,ERROR signal is applied to signals N,C and G,ERROR to drive the indicator 182 clockwise past the overload indicating position toward the stop and automatic clutch indicating position 200. The gain of the N,ERROR signal and the positioning of the stall and automatic clutch position 202 are selected such that the indicator 182 rotates to the stall and automatic clutch indicating position 202 as the engine decelerates toward stall speed under overload conditions. Ru. This typically occurs at about 55% engine speed, which equates to a 45% engine speed error. Display angle 202 is where automatic clutch 20 would normally be disengaged to prevent the engine from stalling completely. In order to further display the degree of overload when the automatic clutch 20 is not disengaged, a red display point 204 is provided in the counterclockwise direction of the stall-first dynamic clutch display position 202. Display unit 182 is red part 20
4 indicates that the engine speed has decreased below the automatic sustained speed and that engine stall is inevitable. For the convenience of the driver, the panel meter 180 may be provided with additional colored coding bands such as 0 and 10.
Engine speed indicators may be provided at shorter intervals than shown in the 0% speed range.

For example, the starting belt 206 can be white between 0 and 40% speed display angles. At 15% of rated speed, fuel is typically allowed to flow during startup and shut off during shutdown. Therefore, the speed reduced fuel to 15% and 55%
Color the red part between the stall speed and the clutch speed,
This can be designated as a fuel zone 208 and can be displayed as a zone where the engine speed through which fuel flows cannot be maintained automatically. This red band completes the red band 204 that indicates when the engine speed drops below the automatic sustain speed while the engine 14 is under load. A yellow band may be provided between the 55% stalled clutch speed indication and the 60% normal no-load operating speed indication.

The speed range between 60% no-load speed and 100% speed is the normal operating speed range for the engine 14 and is typically green.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the power system of a single-wheel gas/tub engine for wheels according to the present invention, and Fig. 2 is a block diagram of a wheel control system used in the power system for car bran shown in Fig. 1. Fig. 3 is a schematic diagram for F shown in Fig. 2, a schematic diagram for function elements, Fig. 4
The figure is a schematic diagram of the F2 function element shown in Figure 2, and Figure 5 is a schematic diagram of the F2 function element shown in Figure 2.
Figure 6 is a schematic diagram of the F5 function element shown in Figure 2, Figure 7 is a graph showing the relationship appropriate to the control system shown in Figure 2, Figure 8 is a schematic diagram of the F3 function element shown in Figure 2. is a schematic diagram of the circuit for the F6 function element shown in Figure 2, Figure 9 is a schematic diagram of the circuit for the F7 function element shown in Figure 2, and Figure 10 is the wheel power system shown in Figure 1. It is a block diagram showing a load meter used together. 10...Power system, 12...Wheel control system, 14...Engine, 16...First reduction gear, 18...First gear Mold drive device, 20・
... Automatic clutch, 22 ... Second gear type drive device, 24 ... Service clutch, 26.
...Transmission device. that. ”・Bure G. 3. Ko G. 3. FuG. 4. Are Ku' Maru G. 6. Ki G. Ku' Furi. 8' AG・〃・fuG・male

Claims (1)

Claims: 1. A single-shaft gas turbine engine that operates in response to an engine speed error signal provided by a vehicle control mechanism and provides an engine speed signal N_1 in response to engine rotational speed; a constant ratio reduction gear connected to receive rotational energy from the engine and output rotational energy with increased torque and reduced rotational speed; receiving rotational energy from the reduction gear and responsive to a clutch control signal; an automatic clutch connected to output rotational energy only when selectively engaged; and an automatic clutch connected between said reduction gearing and the automatic clutch and responsive to energy received from said reduction gearing to provide rotational energy to the vehicle. a drive gearing for a first accessory for driving an accessory; a service clutch connected to receive rotational energy from the automatic clutch and output energy only when selectively engaged by the vehicle operator; a second accessory drive gear connected between the automatic clutch and the service clutch and configured to drive non-essential accessories of the vehicle in response to energy received from the output of the automatic clutch; and a transmission ratio. a control signal and connected to receive rotational energy from the service clutch and providing a rotational energy output to move the vehicle at a rotational speed ratio relative to the received rotational energy in accordance with a transmission ratio control signal and an energy output rotational speed; An infinitely variable transmission that generates a ground speed signal G_1 to be displayed; a signal N_1, a signal G_1, engine exhaust temperature information, an engine speed set signal (N_1 set), a ground speed set signal (G_1 set), and a manual transmission. - manually connected to receive the automatic selection signal and to generate an engine speed error signal of sufficient magnitude to produce the engine speed indicated by the engine speed set signal;
It can operate in a manual mode commanded by an auto-set signal and generates an engine speed error signal that responds to the engine exhaust temperature and causes the engine speed to increase as the load increases toward the desired maximum exhaust temperature. can operate in an automatic mode commanded by a manual-to-automatic selection signal to generating a transmission ratio control signal indicative of the magnitude of the ground speed set signal being less than the difference between the engine speed and the engine speed; a vehicle control mechanism that generates a clutch signal commanding the engagement and disengagement of an automatic clutch when the load meter is greater or less than the actual engine speed; and in automatic mode, a low magnitude display range displays the actual engine speed in response to the signal N_1, and a medium magnitude display range displays the G_1 ERROR signal equal to G_1 and the signal N_1 in response to the actual engine speed plus the reduction in ground speed, and in a higher display range, in response to an error in engine speed to indicate the load that would induce a reduction in engine speed below maximum torque. A power system for a single-shaft gas turbine engine for a vehicle, comprising: a load meter; 2. In the power system set forth in claim 1,
The vehicle control mechanism is a power system for a single-shaft gas turbine engine that includes a minimum ratio circuit for preventing a transmission signal from falling below a predetermined minimum value. 3 In the power system set forth in claim 2,
A power system for a single shaft gas turbine engine, wherein said minimum value is dependent on a ground speed set signal. 4 In the power system set forth in claim 3,
A power system for a single shaft gas turbine engine, wherein the minimum value dictates a transmission ratio for an actual ground speed of about 1/2 of the ground speed at maximum torque engine speed. 5 In the power system set forth in claim 1,
The load meter has signals N_1, N_1ERROR and G_1ERROR at maximum torque engine speed.
A power system for a single shaft gas turbine engine adapted to respond to an N_1 ERROR signal exceeding a limit value by providing a high display range equal to the sum of N_1 ERROR signals. 6 In the power system set forth in claim 1,
A power system for a single shaft gas turbine engine, wherein the predetermined clutch engagement and disengagement engine speeds are both slightly greater than an engine stall speed at which engine operation cannot be maintained. 7 In the power system set forth in claim 1,
The vehicle control mechanism generates a clutch engagement control signal when the engine rotational speed is greater than 55% of the maximum torque engine speed and generates a clutch disengagement control signal when the engine rotational speed is less than 55% of the maximum torque engine speed. A power control system for a single-shaft gas turbine engine. 8 In the power system set forth in claim 7,
A built-in memory that corresponds to a clutch control signal commanding the clutch to be disengaged and prevents generation of a clutch control signal commanding the clutch to engage until the clutch reset signal is actuated by the operator. Power system of a single-shaft gas turbine engine with a circuit.